• Title/Summary/Keyword: nitric oxide synthase activity

Search Result 670, Processing Time 0.035 seconds

Effect of Thesium Chinense Turczaninow on Breast Cancer Chemopreventive enzyme activity in In vitro (In vitro에서의 댑싸리하고초의 유방암예방효소 활성에 미치는 영향)

  • Shon, Yun-Hee;Kim, Mee-Kyung;Park, Sun-Dong;Nam, Kyung-Soo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.20 no.3
    • /
    • pp.675-679
    • /
    • 2006
  • The effect of water extract from Thesium chinese Turczaninow (TCTW) on proliferation of human breast cancer cells, nitric oxide production, nitric oxide synthase expression, and ornithine decarboxylase activity was tested. TCTW inhibited the growth of both estrogen-independent MDA-MB-231 and estrogen-dependent MCF-7 human breast cancer cells. Lipopolysaccharide-induced nitric oxide (NO) production was significantly reduced by TCTW at the concentrations of 1.0 (p<0.05) and 5.0 mg/ml (p<0.005). Expression of inducible nitric oxide synthase (iNOS) was also suppressed with the treatment of TCTW in Western blot analysis. TCTW inhibited induction of ornithine decarboxylase by 12-O-tetradecanoylphorbol-13-acetate (TPA), a key enzyme of polyamine biosynthesis, which is enhanced in tumor promotion. Therefore, TCTW is worth further investigation with respect to breast cancer chernoprevention or therapy.

Elevation of Nitric Oxide Synthase Activity by Dimethyladenosine from Silkworm Pupae in Aged Rats

  • Ahn, Mi-Young;Han, Jea-Woong;Hong, Yoo-Na;Hwang, Jae-Sam
    • Toxicological Research
    • /
    • v.24 no.3
    • /
    • pp.169-174
    • /
    • 2008
  • This study examined the mechanisms underlying the effects of the vasorelaxation active substance(VAS), dimethyladenosine-5'-L-arabinose, and its partial purification fraction on nitric oxide synthase in improving erectile dysfunction with particular focus on the nitric oxide (NO)-cGMP pathways. Two rat models, 9-month-old SD rats and 11-month-old SD rats, were given VAS(40 mg/kg per day) for 4 days, The aqueous fraction of silworm male pupae extract; semi-purified VAS(100 mg/kg per day) for 10 days, respectively. The NOS activities of the following three enzymes were examined: neuronal NO synthase(nNOS), inducible NOS(iNOS), endothelial NOS(eNOS), vascular endothelial growth factor on endothelial cells(VEGF) and anti-inflammation effect of Tumor necrosis factor-$\alpha$. The results showed increases in the nitric oxide synthase activities. Western blotting of the tissue homogenate showed an increase in the nNOS level in the brain and tongue, and an increase in the endothelial NO synthase(eNOS) level in penis. However, there was little association with VEGF production in HUVEC endothelial cells and no relationship with TNF-$\alpha$ which showed low levels.

Anti-inflammatory Effects of Asiaticoside on Inducible Nitric Oxide Synthase and Cyclooxygenase-2 in RAW 264.7 Cell Line (Asiaticoside가 RAW 264,7 세포에서 Inducible nitric oxide synthase와 Cyclooxygenase-2에 미치는 항염증 작용에 관한 연구)

  • 주상섭;배옥남;정진호
    • Toxicological Research
    • /
    • v.19 no.1
    • /
    • pp.33-37
    • /
    • 2003
  • Asiaticoside has been tested for the ability as an anti-inflammatory drug using lipopolysaccharide (LPS)-stimulated macrophage cell line (RAW 264.7 cell). LPS treatment induced dramatically inducible nitric oxide synthase (iNOS) in RAW cells. However, asiaticoside inhibited LPS-stimulated iNOS induction in a concentration-dependent manner. Especially, higher concentrations (>50 $\mu\textrm{M}$) of asiaticoside completely blocked iNOS induction. In addition, LPS-stimulated expression of inducible cyclooxygenase (COX-2) and interleukin-1 $\alpha$ (IL-1 $\alpha$) was inhibited by asiaticoside treatment. Asiaticoside up to 50 $\mu\textrm{M}$ still required to inhibit COX-2 and IL-1 $\alpha$ induced by LPS. Consistent with these findings, treatment with asiaticoside suppressed do novo synthesis and cellular accumulation of prostaglandin $E_2$ to a lesser extent, suggesting that asiaticoside blocked the induction as well as the activity of COX-2 These results suggest the possibility that asiaticoside may be effective therapeutic agents for septic shock and other inflammatory diseases.

Korean red ginseng inhibits arginase and contributes to endothelium-dependent vasorelaxation through endothelial nitric oxide synthase coupling

  • Shin, Woosung;Yoon, Jeongyeon;Oh, Goo Taeg;Ryoo, Sungwoo
    • Journal of Ginseng Research
    • /
    • v.37 no.1
    • /
    • pp.64-73
    • /
    • 2013
  • Korean red ginseng water extract (KG-WE) has known beneficial effects on the cardiovascular system via inducting nitric oxide (NO) production in endothelium. Endothelial arginase inhibits the activity of endothelial nitric oxide synthase (eNOS) by substrate depletion, thereby reducing NO bioavailability and contributing to vascular diseases including hypertension, aging, and atherosclerosis. In the present study, we demonstrate that KG-WE inhibits arginase activity and negatively regulates NO production and reactive oxygen species generation in endothelium. This is associated with increased dimerization of eNOS without affecting the protein expression levels of either arginase or eNOS. In a vascular tension assay, when aortas isolated from wild type mice were incubated with KG-WE, NO-dependent enhanced vasorelaxation was observed. Furthermore, KG-WE administered via by drinking water to atherogenic model mice being fed high cholesterol diet improved impaired vascular function. Taken together, these results suggest that KG-WE may exert vasoprotective effects through augmentation of NO signaling by inhibiting arginase. Therefore, KG-WE may be useful in the treatment of vascular diseases derived from endothelial dysfunction, such as atherosclerosis.

Inhibition of Inducible Nitric Oxide Synthase by Agaricus bisporus Extract in RAW 264.7 Macrophages

  • Ahn, Ji-Yun;Lee, Hyun-Jung;Moon, Mi-Kyung;Kim, Su-Na;Ha, Tae-Youl
    • Preventive Nutrition and Food Science
    • /
    • v.13 no.4
    • /
    • pp.362-365
    • /
    • 2008
  • Agaricus bisporus, also known as white button mushroom, is one of the most popular mushrooms consumed in Korea. This mushroom contains high concentrations of flavanoids and exhibits antioxidant activity. In this study, we examined the effects of Agaricus bisporus ethanol extract (ABE) on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 cells. Nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) protein levels were assessed in cells treated with $100\;{\mu}M$ LPS in the presence or absence of ABE. 0.5 mg/mL of ABE suppressed NO production significantly. Moreover, ABE inhibited levels of iNOS protein. Taken together, these results suggest that ABE exerts anti-inflammatory activity in LPS-induced inflammation in RAW 264.7 cells.

Changes of Specific Activity and Regulation of Nitric Oxide Synthase during Liver Regeneration after Partial Hepatectomy

  • Lee, Young-Jin;Nam, Suk-Woo;Seo, Dong-Wan;An, Sung-Whun;Ko, Young-Kwun;Sung, Dae-Seok;Han, Jung-Whan;Lee, Hyang-Woo
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 1996.04a
    • /
    • pp.185-185
    • /
    • 1996
  • Nitric oxide synthase(NO Synthase:E.C.1.14.13.39)는 생체내에서 L-arginine을 기질로 하여 citrulline과 nitric oxide(NO)를 생성하는 효소로서, 최근 연구에 의하면 2/3 부분 간 절제술 후 prereplicative phase동안에 발현되는 것으로 알려져 있다. 한편, 생체내에서 NO Synthase에 상경적 길항제인 methylarginine에 관해서도 수년간 많은 연구가 진행되어 왔다. 이들의 생성 기전은 protein methylation에 의해 생성된 methylated protein이 생체 내에서 분해되어 생성된다고 알려져 있으나, 정확한 기전에 대해서는 아직 논란의 여지가 많다. 따라서, 본 연구에서는 In vivo 실험을 통해 부분 간 절제술 후 시간대별로 간 조직에서의 NO Synthase 활성도와 혈청에서 NO의 최종 대사물인 Nitrite/Nitrate를 측정하였으며, 또한 NO Synthase 조절에 관여하는 세포내 기질인 arginine과 억제 인자인 methylarginine함량을 간 조직 및 혈청에서 측정하고, 세포 신호 전달체계에 관여하는 cyclic GMP 함량을 측정함으로써, 부분 간 절제술 후 간 재생동안에 NO Synthase 활성도와 methylarginine 및 arginine과의 상관 관계를 규명하고, 간 재생동안, 생성된 nitric oxide의 역할을 연구하려한다.

  • PDF

Down-regulation of inducible nitric oxide synthase and tumor necrosis factor-a expression by Bisphenol A via nuclear factor-kB inactivation in macrophages

  • Kim, Ji-Young;Jeong, Hye-Gwang
    • Proceedings of the PSK Conference
    • /
    • 2002.10a
    • /
    • pp.293.2-293.2
    • /
    • 2002
  • Bisphenol A [BPA. 2.2-bis(4-hydroxyphenyl)propane] is reported to have estrogenic activity: however. its influence on cytokine production or immune system function remains unclear. In this study. we investigated the effects of BPA on the production of nitric oxide (NO) and tumor necrosis factor-a (TNF-a), and on the level of inducible nitric oxide synthase (iNOS) and TNF-a gene expression in mouse macrophages. BPA alone did not affect NO or TNF-a production. (omitted)

  • PDF

Effect of Geraniol on the Proliferation of L1210 Cells and ICR Mouse Macrophages, and the Activities of Superoxide Dismutase (SOD) and Inducible Nitric Oxide Synthase ( iNOS) Activities (Geraniol이 L1210 세포와 ICR 생쥐 대식세포의 증식,Superoxide Dismutase(SOD)와 Inducible Nitric Oxide Synthase(iNOS) 효소활성에 미치는 영향)

  • Kim, Ji-Yeon;Park, Sie-Won
    • YAKHAK HOEJI
    • /
    • v.48 no.6
    • /
    • pp.309-316
    • /
    • 2004
  • The present investigation was undertaken to find out the anticancer activity of monoterpene compounds. Monoterpenes showed generally the inhibitory effect on the proliferation o f L1210 cancer cells (cytotoxicity). Geraniol was found to exibit the most potent cytotoxic effect on L1210 cells with an IC50 values of $0.67{\mu}g/ml$. On the other hand, geraniol proved to be capable of stimulating the macrophage proliferation (135% of control). When the life prolonging activity of geraniol by daily oral administration of 0.1~10${\mu}g/10{\mu}l/20$ g body weight to Sarcoma 180 bearing ICR mouse was examined, there was also a significant elevation of survival (best result of 134% of control). The contradictory effects of geraniol on the proliferation of L1210 cells and macrophages proved to be accompanied by the coincident alterations of RNS (reactive nitrogen species) related enzymes activities such as inducible nitric oxide synthase (Inos) in macrophages and ROS (reactive oxygen species) related enzymes activities such as superoxide dismutase (SOD) in L1210 cells, respectively.

Inhibitory Activity of Chinese Medicinal Plants on Nitric Oxide Synthesis in Lipopolysaccharide -Activated Macrophages

  • Ryu, Jae-Ha;Ahn, Han-Na;Lee, Hwa-Jin;Feng, Li;Qun, Wen-He;Han, Yong-Nam;Han, Byung-Hoon
    • Biomolecules & Therapeutics
    • /
    • v.9 no.3
    • /
    • pp.183-187
    • /
    • 2001
  • Nitric oxide (NO) produced in large amounts by the inducible nitric oxide synthase (iNOS) is known to be responsible for the vasodilation and hypotension observed in septic shock and inflammation. The inhibitors of iNOS, thus, may be useful candidate for the treatment of inflammatory diseases accompanied by the overproduction of NO. We prepared alcoholic extracts of Chinese medicinal plants and screened their inhibitory activity against NO production in lipopolysaccharide (LPS)-activated macrophages. Among the 80 kinds of extracts of herbal drugs, 15 extracts showed potent inhibitory activity of NO production above 80% at the concentration o$50\mu\textrm{g}/ml$. These potent extracts showed dose dependent inhibition of NO production of LPS-activated macrophages at the concentration of 50, 30,$10\mu\textrm{g}/ml$. Especially, Rhus chinensis, Senecio scandens and Wikstroemia indica showed most potent inhibition above 50% at the concentration of $10\mu\textrm{g}/ml$. These plants are promising candidates for the study of the activity-guided purification of active compounds and would be useful for the treatment of inflammatory diseases and endotoxemia accompanying the overproduction of NO.

  • PDF